Hi loss -
I don't know what the 'scanner' you mention is - but for the Hammond organ "leslie" type of sound, MFOS has a module that will simulate that.
For simple vibrato, you can run your lfo thru an attenuator then into the CV input of your VCO...at least that's how I do it.

1.3 Hammond Vibrato
Provided on the organs so equipped are vibrato and chorus settings V1,V2,V3 and C1,C2,C3.

Vibrato is the periodic raising and lowering of the pitch, and is thus fundamentally different from tremolo which is a variation in only the loudness of the pitch. The Hammond vibrato is implemented using a tapped delay line, really a low-pass filter. The signal is applied to the delay line and a rotating scanner, attached to one end of the tone generator assembly, picks the signal off of the delay line at the tap points. The scanner, a single-pole 16-throw air-dielectric capacitor switch, is wired so that the tap point will traverse the entire delay line twice, once up the delay line and once back down, for each scanner rotation. As the delay line is traversed phase is added-to and then subtracted-from the signal.

The chorus signal is produced by adding non-pitch-shifted signal to the pitch-shifted signal.

The three settings each of vibrato and chorus correspond to different amounts of total delay thus different amounts of total pitch shift.

In addition to the pitch shifting function, the vibrato, as implemented in the Hammond organ, also acts as a sweeping low-pass filter. There is some frequency response and amplitude variation as the tap point of the filter is swept.

1.4 The Scanner
The scanner is used in the organ as a single-pole 16-throw rotary switch. It is constructed as a multi-plate air-dielectric capacitor with 16 stator poles and one rotor. It is used, in conjunction with the vibrato delay line, to create the chorus/vibrato.

You can simulate a Hammond chorus/vibrato circuit with an eight-stage delay line, an eight-input crossfader, and a triangle LFO.

The delay line lengths are fixed. The eight outputs are fed into the crossfader, and the crossfader is swept by the LFO. The crossfader alone produces the vibrato effect; mixing it with the original signal produces the chorus.

The lengths of the delay line are pretty critical. The sweet spot isn't very wide.

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